Which term describes a variation of a melody where ascending intervals are replaced by descending intervals?

The term that correctly describes a variation of a melody where ascending intervals are replaced by descending intervals is known as inversion. In musical terms, inversion involves flipping the melody around a central note or pitch, which results in the original ascending patterns being transformed into descending ones. This can give the melody a different character and mood while maintaining its foundational structure.

Understanding inversion is crucial for grasping how melodies can be creatively altered while preserving some of their original attributes. This technique is often used in composition to add variety and depth to musical pieces.